In copending applications Ser. No. 184,192 filed Sept. 5, 1980 and Ser. No. 199,365 filed Oct. 21, 1980 (the disclosures of each of which are incorporated by reference herein), an apparatus is provided which greatly facilitates the application of liquids--especially liquid contact hercibides--to plants. While such apparatus is emminently suited for performing its intended function, if operated on uneven terrain for extended periods of time, there may be a tendency for the elevated portions thereof to become "starved" of liquid, with resultant uneven application to plants. The present invention seeks to overcome such a problem in a simple and effective manner.
According to the present invention, metering means are provided for supplying liquid to a sponge (or like transfer means), which in turn supplies the liquid to the applicator roller, so that if one end of the roller is elevated with respect to the other, liquid will be supplied to the high end of the transfer means and roller. A supply conduit, such as flexible tubing, extends generally along the length of the transfer means and has a plurality of openings in the bottom thereof through which liquid can flow and drip onto high end of the transfer means and roller. A supply conduit, such as flexible tubing, extends generally along the length of the transfer means and has a plurality of openings in the bottom thereof through which liquid can flow and drip onto the transfer means. A housing is disposed in operative engagement with a central portion of the conduit, and means define a pair of opposed sealing surfaces at opposite ends of the housing in communication with a bore in the housing parallel to the applicator roller. A tilt-responsive sealing member, such as metal ball having a diameter smaller than the bore, is mounted within the bore between the sealing surfaces for cooperation with the lowermost of the sealing surfaces to provide sealing therewith when the roller is tilted so that one end thereof is perceptibly higher than the other end.
The metering means according to the invention is extremely simple, and may be designed so that it consists of merely the housing with sealing surfaces an interiorly mounted sealing member, and a supply tube extending into the housing from the top thereof, generally perpendicular to the bore. However where the roller is particularly long, it may be desirable to provide a plurality of central housings spaced from each other along the conduit, with a different supply tube extending to each central housing.
It is the primary object of the present invention to provide a simple and effective structure for supplying liquid to a plant-contacting apparatus even when operated over uneven terrain. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.